The EPB has been used to restrain the movement of a parked vehicle. When the movement of a vehicle is to be restrained, the EPB is activated to exercise lock control in order to place the wheels of the vehicle in a locked state by pressing a brake pad or other friction material against a brake disc or other friction target material to generate a parking brake force. When the restraint on the movement of the vehicle is to be removed, the EPB is activated to exercise release control in order to release the friction material from the friction target material, thereby switching the status of the wheels from the locked state to a released state. As the EPB is capable of generating the parking brake force as described above, studies are conducted to variously exercise vehicle control by using the parking brake force.
However, if the EPB becomes faulty in the locked state while the vehicle is stopped, for instance, at an intersection so that the wheels cannot be released (this state will be hereinafter referred to as the EPB's stuck state or lock stuck state), traffic is obstructed. It is therefore preferred that the vehicle be capable of being moved to a roadside. As such being the case, proposed in PTL 1 is a technology that exercises release control to permit the vehicle to move in the event of a failure in which the EPB is stuck but the wheels are releasable.